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Estimation of Sand Transportation Rate for Fixed and Semi-Fixed Dunes Using Meteorological Wind Data

Pedosphere 2009年第1期19卷 129-136页

作者： HU Xia LIU Lian-You LI Shun-Jiang XIAO Bi-Lin LIU Mu-Xin Key Lab of environment Change and Natural Disaster Ministry of Education Beijing Normal Univeristy Beijing 100875 （China） academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs/Ministry of Education Beijing Normal University Beijing 100875 （China） State Key Laboratory of Soil and sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 21008 （China） institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 （China） institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 （China）

Taibus County, Inner Mongolia, china, lies in a farming-pastoral ecotone, where severe wind erosion and various aeolian sand hazards are prevalent and fixed and semi-fixed sand dunes occur frequently. This study was conducted to investigate the relationships between sand transportation rate and wind speed for the fixed and semi-fixed sand dunes based on field measurements. The annual quantity of soil erosion by wind was estimated using meteorological wind data. The results indicated that the sand transportation rate in Taibus County in 2.00 was 57.38 kg cm-1 year-1 for the semi-fixed dunes and 4.56 kg cm-1 year-1 for the fixed dunes. The total duration of erosive winds covered 12.5% of the time of the year, and spring posed the highest potential of sand transportation. Wind with low speed (≤ 17 m s-1) and high frequency plays a dominant role in sand transportation, while strong wind (≥ 17 m s-1) with low frequency significantly enhanced the sand transportation. Erosive wind speed, directions, and frequency were three crucial dynamic factors influencing sand hazards in the farming-pastoral ecotone. The dominant factors intensifying sand and dust storms in Taibus County might be related to the favorable wind condition in combination with the durable drought, which led to land desertification and vegetation degradation.

关键词： fixed and semi-fixed dunes meteorological wind data sand transportation rate wind erosion

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Monitoring of rice crop using ENVISAT ASAR data

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Science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3 & PANG Yong4 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese {2. of sciences, beijing 100101, china 2. Graduate University of chinese {2. of sciences, beijing 100039, china 3. Department of Geography, University of Maryland, College Park, MD 2.742. USA 4. Forest Remote Sensing Lab, Research institute of Forest Resource and Information Technology, chinese {2. of For-estry, beijing 100091, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Graduate University of chinese academy of {2. Beijing China Department of Geography University of Maryland College Park USA Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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Analysis of developmental Proteome at Egg Stage of Drone Honeybees (A. m. ligustica)

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agricultural sciences in{2. 2010年第3期9卷 392-400页

作者： FANG Yu and LI Jian-ke institute of Apicultural Research, chinese academy of agricultural sciences/Key Laboratory of Pollinating Insect Biology, {2. 100093, P.R.china institute of Apicultural Research Chinese Academy of Agricultural Sciences/Key Laboratory of Pollinating Insect Biology Beijing 100093 P.R.China

An investigation on the proteome of drone egg development of native Italian bee （Apis mellifera ligustica Spinola,1806） was carried out in order to prove up the characteristics in protein expression and regulation at egg stage and open out the molecular mechanism of the development. The experiment was carried out by two-dimensional gel electrophoresis. The results showed that there were 2.0, 2.2.and 2.3 proteins in a wide rang of molecular weight （12.42.169.60 kDa） and in a relatively narrow scope of pI （4.50-9.00） detected on day 1, day 2.and day 3, respectively, during the developmental process of the drone egg. Meanwhile, 164 protein spots were resolved at all the images （i.e., the protein was consistently expressed） along with the egg development, among which 7 were significantly up-expressed （P 〈 0.05） and 4 were significantly down-expressed （P 〈 0.05） while 79 had no significant differences （P 〉 0.05）. In addition, the specific proteins expressing proteins on day 1, day 2.and day 3 were 11, 18 and 18, respectively. Besides, 17 proteins expressed both on day 1 and day 2.but silenced on day 3, and 43 proteins expressed both on day 2.and day 3 but silenced on day 1, while only 8 proteins expressed both on day 1 and day 3 but silenced on day 2. The results indicate that 2.d-old eggs are at the most active expressional stage in the development of drone egg. The protein expressing at all images suggests that it should be indispensable for drone egg development, but their expression pattern is different. The proteins expressing at a specific age of egg suggest that specific proteins are needed in different developmental stages to regulate. And there are more house-keeping proteins in the developmental process of the drone egg than that of worker egg, and it will provide more targets for gene improvement.

关键词： honeybees drone egg two-dimensional gel electrophoresis proteome

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A STUDY ON FIELD WATER CIRCULATION PATTERN IN THE DRYLAND OF NORTHERN china

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Journal of Geographical sciences 1997年第4期7卷 36-43页

作者： Zhong Zhaozhan Zhao Jubao institute of agrometeorology,{2. beijing 100081 People’s Republic of china

Based on the observed data of soil moisture from locating experiments from 1986 to 1990, the pattern of field water circulation in dryland of northern china, where the mean annual precipitation is 300 600 mm, is studied in this paper using the method of water balance. The results show that water satisfying ratio of spring seeding crops is 83.7 90.8 percent and that of winter wheat is about 70 percent in these areas; about 80 90 percent of water consumption of spring seeding crops and about 60 70 percent of water consumption of winter wheat comes from precipitation during the growing period, the rest comes from the soil water storage before the seeding period. But the available soil water is not used thoroughly, about 30 70 percent of available soil water remains unused when the crops are harvested. At the fallow period, the amount of soil water lost by evaporation is very important, which takes up 57 68 percent of precipitation in winter wheat field and 73 2.4 percent in field of spring seeding crops. Thus restraining soil evaporation, raising the storage ratio of natural precipitation and the soil water utilization efficiency of crops, strengthening the circulation ability of soil water by adopting efficient measures of agricultural techniques, are the main ways for exploiting and developing the potential productivity of natural precipitation in these areas.

关键词： crop field water soil evaporation crop water consumption field water circulation dryland

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河北北部和内蒙古东部森林-草原交错带森林景观格局初步研究

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生态学杂志 2004年第3期23卷 11-15页

作者：王庆锁中国农业科学院农业环境与可持续发展研究所北京100081

河北北部、内蒙古东部森林草原交错带的森林景观主要有白桦林、山杨林、云杉林、蒙古栎林和榆树疏林。森林斑块的数量在森林草原交错带的森林草甸区最多 ,其次是森林带 ,再次是森林草原交错带的草甸草原区 ,草原带没有森林斑块。从... 详细信息

河北北部、内蒙古东部森林草原交错带的森林景观主要有白桦林、山杨林、云杉林、蒙古栎林和榆树疏林。森林斑块的数量在森林草原交错带的森林草甸区最多 ,其次是森林带 ,再次是森林草原交错带的草甸草原区 ,草原带没有森林斑块。从森林带到森林草原交错带 ,森林斑块变小、森林景观破碎化程度提高。森林草原交错带森林景观的形成是气候变化和现代气候、地形。

关键词：森林景观分布格局生态交错带森林-草原

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N_2. emissions from agricultural soils in the North china Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2.3 , Dieter Scharffe 2. Manfred Domroes 3, QI Yu chun 1, ZHANG Shen 1 (1. institute of Geographic sciences and Natural Resources Research, {2. academy of sciences, beijing 100101, china E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North china Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1—2..1, the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1 μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North china Plain agricultural soils chemical nitrogen organic manure

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OsWRKY03, a rice transcriptional activator that functions in defense signaling pathway upstream of OsNPR1

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Cell Research 2005年第8期15卷 593-603页

作者： Xiao Qiang LIU1,2. Xian Quan BAI1,2. Qian QIAN3, Xiu Jie WANG1, Ming Sheng CHEN1, Cheng Cai CHU1,* 1National Key Laboratory of Plant Genomics, institute of Genetics and developmental Biology, {2. academy of sciences, beijing 100101, china 2.raduate School of the {2. academy of sciences, Yuquan Road, beijing 100039, china 3{12. National Rice Research institute, chinese academy of agricultural sciences, Hangzhou 310006, china National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of {2. Yuquan Road Beijing China china National Rice Research institute Chinese Academy of Agricultural Sciences Hangzhou China

WRKY family proteins are a class of plant specific transcription factors that involve in many stress response pathways. It has been shown that one Arabidopsis WRKY protein, AtWRKY2./2., is activated by MAP kinase signaling cascade and confers resistance to both bacterial and fungal pathogens. However, little is known about the biological roles of WRKY proteins in rice. In this study, we investigated the expression patterns of rice AtWRKY2./2. homolog, OsWRKY03, under different conditions, and also its possible role involved in plant defense. Our results showed that OsWRKY03 was up-regulated by several defense signaling molecules or different treatments. Further analysis revealed that the expres- sion of OsWRKY03 was light dependent. Transcriptional activation activity of OsWRKY03 was also demonstrated by yeast functional assay. Transient expression of OsWRKY03-GFP fusion protein in onion epidermis cells showed that OsWRKY03 was a nuclear localized protein. OsNPR1 as well as several other pathogenesis-related genes, such as OsPR1b, phenylalanine ammonia-lyase (ZB8) and peroxidase (POX2..3), were induced in OsWRKY03-overexpressing transgenic plants. These results indicated that OsWRKY03 is located upstream of OsNPR1 as a transcriptional activator in salicylic acid (SA)-dependent or jasmonic acid (JA)-dependent defense signaling cascades.

关键词： defense response OsWRKY03 transcription factor rice.

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The comprehensive evaluation of sustainabledevelopment in karst regions-Taking Shishanareas in Guangxi of{2. as an example

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Journal of Geographical sciences 1999年第3期9卷 301-306页

作者： REN Dong-ming1, HU Bao-qing2.1. institute of Geography chinese {2. of sciences, beijing 100101, china, 2. institute ofGeotectonics, chinese {2. of sciences, Changsha 410013, china)

This paper works out a practical evaluation method of sustainable development for theundeveloped the regions and take Shishan areas of Guangxi Zhuang Autonomous Region of{2.as an example. First of all, according to the actual conditions of the karst regions in Guangxi and thetheory of regional sustainable development this paper estabishes an index system of comprehensiveevaluation, then takes twenty-eight representative cities and counties within the karst regions ofGuangxi as research objects to evaluate the level of sustainable development. It basically illustratesthe state of regional sustainable development of the karst regions in Guangxi.

关键词： Karst regions Shishan areas, Guangxi, sustainable development index system

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Analysis of the essential DNA region for OsEBP-89 promoter in response to methyl jasmonic acid

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Science china(Life sciences) 2008年第3期51卷 280-285页

作者： LI Ang1,2. CHEN LiangLiang1,3, REN HaiYun3, WANG XueChen2. ZHANG HaiWen1,4 & HUANG Rong- Feng1,4 1 Biotechnology Research institute, chinese academy of agricultural sciences,{2., china 2.National Laboratory of Plant Physiology and Biochemistry, College of Biological sciences, china agricultural University, beijing 100094, china 3 College of Life sciences, beijing Normal University, beijing 100875, china 4 National Key Facility of Crop Gene Resources and Genetic Improvement,{2., china Biotechnology Research institute Chinese Academy of Agricultural Sciences Beijing China National Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing China College of Life sciences Beijing Normal University Beijing China National Key Facility of Crop Gene Resources and Genetic Improvement Beijing China

In rice, the characterization of OsEBP-89 is inducible by various stress- or hormone-stimuli, including ethylene, abscisic acid (ABA), jasmonate acid (JA), drought and cold. Here, we report the investigation of essential DNA region within OsEBP-89 promoter for methyl jasmonic acid (MeJA) induction. PLACE analysis indicates that this promoter sequence contains multiple potential elements in response to various stimuli. First, we fused this promoter with GUS gene and analyzed its expression under MeJA treatment through agrobacterium infiltration mediating transient expression in tobacco leaves. Our results revealed that this chimeric gene could be inducible by MeJA in tobacco leaves. To further de- termine the crucial sequences responsible for MeJA induction, we generated a series of deletion pro- moters which were fused with GUS reporter gene respectively. The results of transient expression of GUS gene driven by these mutant promoters show that the essential region for MeJA induction is po- sitioned in the region between -12.0 and -800 in OsEBP-89 promoter containing a G-box (?112.), which is distinct from the essential region containing ERE (?562. for ACC induction. In all, our finding is helpful in understanding the molecular mechanism of OsEBP-89 expression under different stimuli.

关键词： OsEBP-89 essential DNA region methyl jasmonic acid transient assay promoter tobacco leaves

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Evolution of plant microRNA gene families

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Cell Research 2007年第3期17卷 212-218页

作者： Aili Li~1 Long Mao~(1,2. ~1institute of Crop sciences,{2. academy of agricultural sciences and The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI),Beoing 100081,china ~2.epartment of Biological sciences,Northern Illinois University,DeKalb,IL 60115,USA institute of Crop sciences Chinese Academy of Agricultural Sciences and The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI) Beijing China Department of Biological sciences Northern Illinois University DeKalb USA

MicroRNAs(miRNAs)are important post-transcriptional regulators of their target genes in plants and animals,miR-NAs are usually 2.-2. nucleotides *** their unusually small sizes,the evolutionary history of miRNA genefamilies seems to be similar to their protein-coding *** contrast to the small but abundant miRNA familiesin the animal genomes,plants have fewer but larger miRNA gene *** of plant miRNA gene familiesare often highly similar,suggesting recent expansion via tandem gene duplication and segmental duplication *** many miRNA genes are conserved across plant species,the same gene family varies significantly in size andgenomic organization in different species,which may cause dosage effects and spatial and temporal differences in targetgene *** this review,we summarize the current progress in understanding the evolution of plant miRNA genefamilies.

关键词： microRNAs post-transcriptional regulation tandem duplication segmental duplication

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